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Nilsson KH, Henning P, Wu J, Sjögren K, Lerner UH, Ohlsson C, Movérare-Skrtic S. GREM2 inactivation increases trabecular bone mass in mice. Sci Rep 2024; 14:12967. [PMID: 38839844 PMCID: PMC11153596 DOI: 10.1038/s41598-024-63439-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 05/29/2024] [Indexed: 06/07/2024] Open
Abstract
Osteoporosis is a common skeletal disease affecting millions of individuals world-wide, with an increased risk of fracture, and a decreased quality of life. Despite its well-known consequences, the etiology of osteoporosis and optimal treatment methods are not fully understood. Human genetic studies have identified genetic variants within the FMN2/GREM2 locus to be associated with trabecular volumetric bone mineral density (vBMD) and vertebral and forearm fractures, but not with cortical bone parameters. GREM2 is a bone morphogenetic protein (BMP) antagonist. In this study, we employed Grem2-deficient mice to investigate whether GREM2 serves as the plausible causal gene for the fracture signal at the FMN2/GREM2 locus. We observed that Grem2 is moderately expressed in bone tissue and particularly in osteoblasts. Complete Grem2 gene deletion impacted mouse survival and body growth. Partial Grem2 inactivation in Grem2+/- female mice led to increased trabecular BMD of femur and increased trabecular bone mass in tibia due to increased trabecular thickness, with an unchanged cortical thickness, as compared with wildtype littermates. Furthermore, Grem2 inactivation stimulated osteoblast differentiation, as evidenced by higher alkaline phosphatase (Alp), osteocalcin (Bglap), and osterix (Sp7) mRNA expression after BMP-2 stimulation in calvarial osteoblasts and osteoblasts from the long bones of Grem2-/- mice compared to wildtype littermates. These findings suggest that GREM2 is a possible target for novel osteoporotic treatments, to increase trabecular bone mass and prevent osteoporotic fractures.
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Affiliation(s)
- Karin H Nilsson
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Osteoporosis Centre, Centre for Bone and Arthritis Research at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
| | - Petra Henning
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Osteoporosis Centre, Centre for Bone and Arthritis Research at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Jianyao Wu
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Osteoporosis Centre, Centre for Bone and Arthritis Research at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Klara Sjögren
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Osteoporosis Centre, Centre for Bone and Arthritis Research at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Ulf H Lerner
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Osteoporosis Centre, Centre for Bone and Arthritis Research at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Claes Ohlsson
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Osteoporosis Centre, Centre for Bone and Arthritis Research at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Drug Treatment, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Sofia Movérare-Skrtic
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Osteoporosis Centre, Centre for Bone and Arthritis Research at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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Huynh NV, Rehage C, Hyndman KA. Mild dehydration effects on the murine kidney single-nucleus transcriptome and chromatin accessibility. Am J Physiol Renal Physiol 2023; 325:F717-F732. [PMID: 37767569 DOI: 10.1152/ajprenal.00161.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 09/12/2023] [Accepted: 09/19/2023] [Indexed: 09/29/2023] Open
Abstract
Daily, we may experience mild dehydration with a rise in plasma osmolality that triggers the release of vasopressin. Although the effect of dehydration is well characterized in collecting duct principal cells (CDPCs), we hypothesized that mild dehydration (<12 h) results in many kidney cell-specific changes in transcriptomes and chromatin accessibility. Single-nucleus (sn) multiome (RNA-assay for transposase-accessible chromatin) sequencing and bulk RNA sequencing of kidneys from male and female mice that were mildly water deprived or not were compared. Water-deprived mice had a significant increase in plasma osmolality. sn-multiome-seq resulted in 19,837 nuclei that were annotated into 33 clusters. In CDPCs, aquaporin 2 (Aqp2) and aquaporin 3 (Apq3) were greater in dehydrated mice, but there were novel genes like gremlin 2 (Grem2; a cytokine) that were increased compared with ad libitum mice. The transcription factor cAMP-responsive element modulator (Crem) was greater in CDPCs of dehydrated mice, and the Crem DNA motif was more accessible. There were hundreds of sex- and dehydration-specific differentially expressed genes (DEGs) throughout the kidney, especially in the proximal tubules and thin limbs. In male mice, DEGs were enriched in pathways related to lipid metabolism, whereas female DEGs were enriched in organic acid metabolism. Many highly expressed genes had a positive correlation with increased chromatin accessibility, and mild dehydration exerted many transcriptional changes that we detected at the chromatin level. Even with a rise in plasma osmolality, male and female kidneys have distinct transcriptomes suggesting that there may be diverse mechanisms used to remain in fluid balance.NEW & NOTEWORTHY The kidney consists of >30 cell types that work collectively to maintain fluid-electrolyte balance. Kidney single-nucleus transcriptomes and chromatin accessibility profiles from male and female control (ad libitum water and food) or mildly dehydrated mice (ad libitum food, water deprivation) were determined. Mild dehydration caused hundreds of cell- and sex-specific transcriptomic changes, even though the kidney function to conserve water was the same.
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Affiliation(s)
- Nha Van Huynh
- Section of Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Cassidy Rehage
- Section of Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Kelly A Hyndman
- Section of Cardio-Renal Physiology and Medicine, Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
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Bottasso-Arias N, Leesman L, Burra K, Snowball J, Shah R, Mohanakrishnan M, Xu Y, Sinner D. BMP4 and Wnt signaling interact to promote mouse tracheal mesenchyme morphogenesis. Am J Physiol Lung Cell Mol Physiol 2022; 322:L224-L242. [PMID: 34851738 PMCID: PMC8794023 DOI: 10.1152/ajplung.00255.2021] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Tracheobronchomalacia and complete tracheal rings are congenital malformations of the trachea associated with morbidity and mortality for which the etiology remains poorly understood. Epithelial expression of Wls (a cargo receptor mediating Wnt ligand secretion) by tracheal cells is essential for patterning the embryonic mouse trachea's cartilage and muscle. RNA sequencing indicated that Wls differentially modulated the expression of BMP signaling molecules. We tested whether BMP signaling, induced by epithelial Wnt ligands, mediates cartilage formation. Deletion of Bmp4 from respiratory tract mesenchyme impaired tracheal cartilage formation that was replaced by ectopic smooth muscle, recapitulating the phenotype observed after epithelial deletion of Wls in the embryonic trachea. Ectopic muscle was caused in part by anomalous differentiation and proliferation of smooth muscle progenitors rather than tracheal cartilage progenitors. Mesenchymal deletion of Bmp4 impaired expression of Wnt/β-catenin target genes, including targets of WNT signaling: Notum and Axin2. In vitro, recombinant (r)BMP4 rescued the expression of Notum in Bmp4-deficient tracheal mesenchymal cells and induced Notum promoter activity via SMAD1/5. RNA sequencing of Bmp4-deficient tracheas identified genes essential for chondrogenesis and muscle development coregulated by BMP and WNT signaling. During tracheal morphogenesis, WNT signaling induces Bmp4 in mesenchymal progenitors to promote cartilage differentiation and restrict trachealis muscle. In turn, Bmp4 differentially regulates the expression of Wnt/β-catenin targets to attenuate mesenchymal WNT signaling and to further support chondrogenesis.
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Affiliation(s)
- Natalia Bottasso-Arias
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
| | - Lauren Leesman
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
| | - Kaulini Burra
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
| | - John Snowball
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
| | - Ronak Shah
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio,2University of Cincinnati Honors Program, Cincinnati, Ohio
| | - Megha Mohanakrishnan
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio,2University of Cincinnati Honors Program, Cincinnati, Ohio
| | - Yan Xu
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio,3Universtiy of Cincinnati, College of Medicine, Cincinnati, Ohio
| | - Debora Sinner
- 1Neonatology and Pulmonary Biology Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio,3Universtiy of Cincinnati, College of Medicine, Cincinnati, Ohio
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Krishnapati LS, Khade S, Trimbake D, Patwardhan R, Nadimpalli SK, Ghaskadbi S. Differential expression of BMP inhibitors gremlin and noggin in Hydra suggests distinct roles during budding and patterning of tentacles. Dev Dyn 2020; 249:1470-1485. [PMID: 33245611 DOI: 10.1002/dvdy.238] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 07/22/2020] [Accepted: 08/05/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Mechanisms regulating BMP and Wnt pathways and their interactions are not well studied in Hydra. RESULTS We report identification of BMP inhibitor gremlin, comparison of its expression with that of noggin and possible antagonism between Wnt and BMP signaling in Hydra. Gremlin is expressed in body column with high levels in budding region and in early buds. Noggin, on the other hand, is expressed in the hypostome, base of tentacles, lower body column, and basal disc. During budding, noggin is expressed at the sites of tentacle emergence. This was confirmed in ectopic tentacles in polyps treated with alsterpaullone (ALP), a GSK-3β inhibitor that leads to upregulation of Wnt pathway. RT-PCR data show that upregulation of Wnt is accompanied by downregulation of bmp 5-8b though noggin and gremlin remain unaltered till 24 hours. CONCLUSIONS Different expression patterns of gremlin and noggin suggest their roles in budding and patterning of tentacles, respectively. Further, bmp 5-8b inhibition by activated Wnt signaling does not directly involve noggin and gremlin in Hydra. Our data suggest that Wnt/BMP antagonism may have evolved early for defining the oral-aboral axis, while the involvement of BMP antagonists during axial patterning is a recent evolutionary acquisition within the Bilateria lineage.
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Affiliation(s)
- Lakshmi Surekha Krishnapati
- Developmental Biology Group, MACS-Agharkar Research Institute, Pune, India.,Laboratory for Protein Biochemistry and Glycobiology, Biochemistry Department, University of Hyderabad, Hyderabad, India
| | - Samiksha Khade
- Developmental Biology Group, MACS-Agharkar Research Institute, Pune, India
| | - Diptee Trimbake
- Developmental Biology Group, MACS-Agharkar Research Institute, Pune, India
| | - Rohan Patwardhan
- Developmental Biology Group, MACS-Agharkar Research Institute, Pune, India
| | - Siva Kumar Nadimpalli
- Laboratory for Protein Biochemistry and Glycobiology, Biochemistry Department, University of Hyderabad, Hyderabad, India
| | - Surendra Ghaskadbi
- Developmental Biology Group, MACS-Agharkar Research Institute, Pune, India
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Bertrand AA, Malapati SH, Yamaguchi DT, Lee JC. The Intersection of Mechanotransduction and Regenerative Osteogenic Materials. Adv Healthc Mater 2020; 9:e2000709. [PMID: 32940024 PMCID: PMC7864218 DOI: 10.1002/adhm.202000709] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 06/14/2020] [Indexed: 12/23/2022]
Abstract
Mechanical signals play a central role in cell fate determination and differentiation in both physiologic and pathologic circumstances. Such signals may be delivered using materials to generate discrete microenvironments for the purposes of tissue regeneration and have garnered increasing attention in recent years. Unlike the addition of progenitor cells or growth factors, delivery of a microenvironment is particularly attractive in that it may reduce the known untoward consequences of the former two strategies, such as excessive proliferation and potential malignant transformation. Additionally, the ability to spatially modulate the fabrication of materials allows for the creation of multiple microenvironments, particularly attractive for regenerating complex tissues. While many regenerative materials have been developed and tested for augmentation of specific cellular responses, the intersection between cell biology and material interactions have been difficult to dissect due to the complexity of both physical and chemical interactions. Specifically, modulating materials to target individual signaling pathways is an avenue of interdisciplinary research that may lead to a more effective method of optimizing regenerative materials. In this work, the aim is to summarize the major mechanotransduction pathways for osteogenic differentiation and to consolidate the known materials and material properties that activate such pathways.
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Affiliation(s)
- Anthony A. Bertrand
- Division of Plastic and Reconstructive Surgery, University of California Los Angeles David Geffen School of Medicine, Los Angeles, California
| | - Sri Harshini Malapati
- Division of Plastic and Reconstructive Surgery, University of California Los Angeles David Geffen School of Medicine, Los Angeles, California
| | - Dean T. Yamaguchi
- Division of Plastic and Reconstructive Surgery, University of California Los Angeles David Geffen School of Medicine, Los Angeles, California
- Research Service, Greater Los Angeles VA Healthcare System, Los Angeles, California
| | - Justine C. Lee
- Division of Plastic and Reconstructive Surgery, University of California Los Angeles David Geffen School of Medicine, Los Angeles, California
- Research Service, Greater Los Angeles VA Healthcare System, Los Angeles, California
- UCLA Molecular Biology Institute, Los Angeles, California
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Lu L, Huang J, Xu F, Xiao Z, Wang J, Zhang B, David NV, Arends D, Gu W, Ackert-Bicknell C, Sabik OL, Farber CR, Quarles LD, Williams RW. Genetic Dissection of Femoral and Tibial Microarchitecture. JBMR Plus 2019; 3:e10241. [PMID: 31844829 PMCID: PMC6894729 DOI: 10.1002/jbm4.10241] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 09/09/2019] [Accepted: 09/16/2019] [Indexed: 12/29/2022] Open
Abstract
Our understanding of the genetic control of bone strength has relied mainly on estimates of bone mineral density. Here we have mapped genetic factors that influence femoral and tibial microarchitecture using high‐resolution x‐ray computed tomography (8‐μm isotropic voxels) across a family of 61 BXD strains of mice, roughly 10 isogenic cases per strain and balanced by sex. We computed heritabilities for 25 cortical and trabecular traits. Males and females have well‐matched heritabilities, ranging from 0.25 to 0.75. We mapped 16 genetic loci most of which were detected only in females. There is also a bias in favor of loci that control cortical rather than trabecular bone. To evaluate candidate genes, we combined well‐established gene ontologies with bone transcriptome data to compute bone‐enrichment scores for all protein‐coding genes. We aligned candidates with those of human genome‐wide association studies. A subset of 50 strong candidates fell into three categories: (1) experimentally validated genes already known to modulate bone function (Adamts4, Ddr2, Darc, Adam12, Fkbp10, E2f6, Adam17, Grem2, Ifi204); (2) candidates without any experimentally validated function in bone (eg, Greb1, Ifi202b), but linked to skeletal phenotypes in human cohorts; and (3) candidates that have high bone‐enrichment scores, but for which there is not yet any functional link to bone biology or skeletal system disease (including Ifi202b, Ly9, Ifi205, Mgmt, F2rl1, Iqgap2). Our results highlight contrasting genetic architecture between sexes and among major bone compartments. The alignment of murine and human data facilitates function analysis and should prove of value for preclinical testing of molecular control of bone structure. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Lu Lu
- Department of Genetics, Genomics and Informatics University of Tennessee Health Science Center Memphis TN USA
| | - Jinsong Huang
- Department of Genetics, Genomics and Informatics University of Tennessee Health Science Center Memphis TN USA
| | - Fuyi Xu
- Department of Genetics, Genomics and Informatics University of Tennessee Health Science Center Memphis TN USA
| | - Zhousheng Xiao
- Department of Medicine University of Tennessee Health Science Center Memphis TN USA
| | - Jing Wang
- Department of Molecular and Human Genetics Baylor College of Medicine Houston TX USA
| | - Bing Zhang
- Department of Molecular and Human Genetics Baylor College of Medicine Houston TX USA
| | - Nicolae Valentin David
- Department of Medicine Northwestern University Feinberg School of Medicine Chicago IL USA
| | - Danny Arends
- Breeding Biology and Molecular Animal Breeding Humboldt University Berlin Germany
| | - Weikuan Gu
- Department of Orthopaedic Surgery and Biomedical Engineering University of Tennessee Health Science Center Memphis TN USA
| | | | - Olivia L Sabik
- Center for Public Health Genomics University of Virginia Charlottesville VA USA
| | - Charles R Farber
- Center for Public Health Genomics University of Virginia Charlottesville VA USA
| | - Leigh Darryl Quarles
- Department of Medicine University of Tennessee Health Science Center Memphis TN USA
| | - Robert W Williams
- Department of Genetics, Genomics and Informatics University of Tennessee Health Science Center Memphis TN USA
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Interaction of tankyrase and peroxiredoxin II is indispensable for the survival of colorectal cancer cells. Nat Commun 2017; 8:40. [PMID: 28659575 PMCID: PMC5489516 DOI: 10.1038/s41467-017-00054-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 05/02/2017] [Indexed: 12/16/2022] Open
Abstract
Mammalian 2-Cys peroxiredoxin (Prx) enzymes are overexpressed in most cancer tissues, but their specific signaling role in cancer progression is poorly understood. Here we demonstrate that Prx type II (PrxII) plays a tumor-promoting role in colorectal cancer by interacting with a poly(ADP-ribose) polymerase (PARP) tankyrase. PrxII deletion in mice with inactivating mutation of adenomatous polyposis coli (APC) gene reduces intestinal adenomatous polyposis via Axin/β-catenin axis and thereby promotes survival. In human colorectal cancer cells with APC mutations, PrxII depletion consistently reduces the β-catenin levels and the expression of β-catenin target genes. Essentially, PrxII depletion hampers the PARP-dependent Axin1 degradation through tankyrase inactivation. Direct binding of PrxII to tankyrase ARC4/5 domains seems to be crucial for protecting tankyrase from oxidative inactivation. Furthermore, a chemical compound targeting PrxII inhibits the expansion of APC-mutant colorectal cancer cells in vitro and in vivo tumor xenografts. Collectively, this study reveals a redox mechanism for regulating tankyrase activity and implicates PrxII as a targetable antioxidant enzyme in APC-mutation-positive colorectal cancer. 2-Cys peroxiredoxin (Prx) enzymes are highly expressed in most cancers but how they promote cancer progression is unclear. Here the authors show that in colorectal cancers with APC mutation, PrxII binds to tankyrase and prevents its oxidative inactivation, thereby preventing Axin1-dependent degradation of ²b-catenin.
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Seo DK, Kim JH, Min J, Yoon HH, Shin ES, Kim SW, Jeon SR. Enhanced axonal regeneration by transplanted Wnt3a-secreting human mesenchymal stem cells in a rat model of spinal cord injury. Acta Neurochir (Wien) 2017; 159:947-957. [PMID: 28160063 DOI: 10.1007/s00701-017-3097-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 01/19/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND While pure mesenchymal stem cell (MSC) treatment for spinal cord injury (SCI) is known to be safe, its efficacy is insufficient. Therefore, gene-modified stem cells are being developed to enhance the effect of pure MSCs. We investigated the effect of stem cell therapy through the transfection of a Wnt3a-producing gene that stimulates axonal regeneration. METHOD MSCs obtained from the human umbilical cord blood (hMSCs) were multiplied, cultivated, and transfected with the pLenti-Wnt3a-GFP viral vector to produce Wnt3a-secreting hMSCs. A total of 50 rats were injured with an Infinite Horizon impactor at the level of the T7-8 vertebrae. Rats were divided into five groups according to the transplanted material: (1) phosphate-buffered saline injection group (sham group, n = 10); (Pertz et al. Proc Natl Acad Sci USA 105:1931-1936, 39) Wnt3a protein injection group (Wnt3a protein group, n = 10); (3) hMSC transplantation group (MSC group, n = 10); (4) hMSCs transfected with the pLenti vector transplantation group (pLenti-MSC group, n = 10); (5) hMSCs transfected with the pLenti+Wnt3a vector transplantation group (Wnt3a-MSC group, n = 10). Behavioral tests were performed daily for the first 3 days after injury and then weekly for 8 weeks. The injured spinal cords were extracted, and axonal regeneration markers including choline acetyltransferase (ChAT), growth-associated protein 43 (GAP43), and microtubule-associated protein 2 (MAP2) were investigated by immunofluorescence, RT-PCR, and western blotting. RESULTS Seven weeks after the transplantation (8 weeks after SCI), rats in the Wnt3a-MSC group achieved significantly higher average scores in the motor behavior tests than those in the other groups (p < 0.05). Immunofluorescent stains showed greater immunoreactivity of ChAT, GAP43, and MAP2 in the Wnt3a-MSC group than in the other groups. RT-PCR and western blots revealed greater expression of these proteins in the Wnt3a-MSC group than in the other groups (p < 0.05). CONCLUSIONS Wnt3a-secreting hMSC transplantation considerably improved neurological recovery and axonal regeneration in a rat SCI model.
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Nielson CM, Liu CT, Smith AV, Ackert-Bicknell CL, Reppe S, Jakobsdottir J, Wassel C, Register TC, Oei L, Alonso N, Oei EH, Parimi N, Samelson EJ, Nalls MA, Zmuda J, Lang T, Bouxsein M, Latourelle J, Claussnitzer M, Siggeirsdottir K, Srikanth P, Lorentzen E, Vandenput L, Langefeld C, Raffield L, Terry G, Cox AJ, Allison MA, Criqui MH, Bowden D, Ikram MA, Mellstrom D, Karlsson MK, Carr J, Budoff M, Phillips C, Cupples LA, Chou WC, Myers RH, Ralston SH, Gautvik KM, Cawthon PM, Cummings S, Karasik D, Rivadeneira F, Gudnason V, Orwoll ES, Harris TB, Ohlsson C, Kiel DP, Hsu YH. Novel Genetic Variants Associated With Increased Vertebral Volumetric BMD, Reduced Vertebral Fracture Risk, and Increased Expression of SLC1A3 and EPHB2. J Bone Miner Res 2016; 31:2085-2097. [PMID: 27476799 PMCID: PMC5477772 DOI: 10.1002/jbmr.2913] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 06/22/2016] [Accepted: 07/08/2016] [Indexed: 12/26/2022]
Abstract
Genome-wide association studies (GWASs) have revealed numerous loci for areal bone mineral density (aBMD). We completed the first GWAS meta-analysis (n = 15,275) of lumbar spine volumetric BMD (vBMD) measured by quantitative computed tomography (QCT), allowing for examination of the trabecular bone compartment. SNPs that were significantly associated with vBMD were also examined in two GWAS meta-analyses to determine associations with morphometric vertebral fracture (n = 21,701) and clinical vertebral fracture (n = 5893). Expression quantitative trait locus (eQTL) analyses of iliac crest biopsies were performed in 84 postmenopausal women, and murine osteoblast expression of genes implicated by eQTL or by proximity to vBMD-associated SNPs was examined. We identified significant vBMD associations with five loci, including: 1p36.12, containing WNT4 and ZBTB40; 8q24, containing TNFRSF11B; and 13q14, containing AKAP11 and TNFSF11. Two loci (5p13 and 1p36.12) also contained associations with radiographic and clinical vertebral fracture, respectively. In 5p13, rs2468531 (minor allele frequency [MAF] = 3%) was associated with higher vBMD (β = 0.22, p = 1.9 × 10-8 ) and decreased risk of radiographic vertebral fracture (odds ratio [OR] = 0.75; false discovery rate [FDR] p = 0.01). In 1p36.12, rs12742784 (MAF = 21%) was associated with higher vBMD (β = 0.09, p = 1.2 × 10-10 ) and decreased risk of clinical vertebral fracture (OR = 0.82; FDR p = 7.4 × 10-4 ). Both SNPs are noncoding and were associated with increased mRNA expression levels in human bone biopsies: rs2468531 with SLC1A3 (β = 0.28, FDR p = 0.01, involved in glutamate signaling and osteogenic response to mechanical loading) and rs12742784 with EPHB2 (β = 0.12, FDR p = 1.7 × 10-3 , functions in bone-related ephrin signaling). Both genes are expressed in murine osteoblasts. This is the first study to link SLC1A3 and EPHB2 to clinically relevant vertebral osteoporosis phenotypes. These results may help elucidate vertebral bone biology and novel approaches to reducing vertebral fracture incidence. © 2016 American Society for Bone and Mineral Research.
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Affiliation(s)
- Carrie M Nielson
- School of Public Health, Oregon Health & Science University, Portland, OR, USA
| | - Ching-Ti Liu
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
| | - Albert V Smith
- Icelandic Heart Association, Kopavogur, Iceland
- Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | | | - Sjur Reppe
- Department of Medical Biochemistry, Oslo University Hospital, Ullevål, Oslo, Norway
- Lovisenberg Diakonale Hospital, Oslo, Norway
- Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | | | - Christina Wassel
- Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, USA
| | - Thomas C Register
- Department of Pathology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Ling Oei
- Internal Medicine, Erasmus MC, Rotterdam, The Netherlands
- Netherlands Genomics Initiative (NGI)-sponsored Netherlands Consortium for Healthy Aging (NCHA), Leiden, The Netherlands
| | - Nerea Alonso
- Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, Scotland, UK
| | - Edwin H Oei
- Radiology & Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Neeta Parimi
- California Pacific Medical Center Research Institute, San Francisco, CA, USA
| | - Elizabeth J Samelson
- Institute for Aging Research, Hebrew SeniorLife, Harvard Medical School, Boston, MA, USA
| | - Mike A Nalls
- National Institute on Aging (NIA), National Institutes of Health, Bethesda, MD, USA
| | - Joseph Zmuda
- Department of Epidemiology, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA, USA
| | - Thomas Lang
- Department of Radiology, University of California, San Francisco (UCSF) School of Medicine, San Francisco, CA, USA
| | - Mary Bouxsein
- Center for Advanced Orthopedic Studies, Beth Israel Deaconess Medical Center, Harvard University Medical School, Boston, MA, USA
| | | | - Melina Claussnitzer
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard University Medical School, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Technical University Munich, Munich, Germany
| | | | - Priya Srikanth
- School of Public Health, Oregon Health & Science University, Portland, OR, USA
| | - Erik Lorentzen
- Department of Bioinformatics, Gothenburg University, Gothenburg, Sweden
| | - Liesbeth Vandenput
- Centre for Bone and Arthritis Research, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Carl Langefeld
- Public Health Sciences, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Laura Raffield
- Center for Human Genomics, Wake Forest School of Medicine, Winston-Salem, NC, USA
- Center for Diabetes Research, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Greg Terry
- Department of Radiology & Radiological Sciences, Vanderbilt University Medical Center, Vanderbilt University, Nashville, TN, USA
| | - Amanda J Cox
- Center for Diabetes Research, Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - Matthew A Allison
- Department of Family Medicine and Public Health, University of California, San Diego (UCSD), La Jolla, CA, USA
| | - Michael H Criqui
- Department of Family Medicine and Public Health, University of California, San Diego (UCSD), La Jolla, CA, USA
| | - Don Bowden
- Center for Diabetes Research, Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, NC, USA
- Internal Medicine/Endocrinology, Wake Forest School of Medicine, Winston-Salem, NC, USA
- Center for Genomics and Personalized Medicine Research, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - M Arfan Ikram
- Department of Epidemiology, Erasmus MC, Rotterdam, The Netherlands
| | - Dan Mellstrom
- Centre for Bone and Arthritis Research, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Magnus K Karlsson
- Department of Orthopaedics and Clinical Sciences, Malmo University Hospital, Lund University, Malmo, Sweden
| | - John Carr
- Department of Radiology & Radiological Sciences, Vanderbilt University Medical Center, Vanderbilt University, Nashville, TN, USA
| | - Matthew Budoff
- Los Angeles Biomedical Research Institute, Torrance, CA, USA
| | - Caroline Phillips
- National Institute on Aging (NIA), National Institutes of Health, Bethesda, MD, USA
| | - L Adrienne Cupples
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
| | - Wen-Chi Chou
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | | | - Stuart H Ralston
- Rheumatic Diseases Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, Scotland, UK
| | - Kaare M Gautvik
- Lovisenberg Diakonale Hospital, Oslo, Norway
- Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Peggy M Cawthon
- California Pacific Medical Center Research Institute, San Francisco, CA, USA
- Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, USA
| | - Steven Cummings
- California Pacific Medical Center Research Institute, San Francisco, CA, USA
| | - David Karasik
- Institute for Aging Research, Hebrew SeniorLife, Harvard Medical School, Boston, MA, USA
- Faculty of Medicine in the Galilee, Bar-Ilan University, Safed, Israel
| | - Fernando Rivadeneira
- Department of Epidemiology, Erasmus MC, Rotterdam, The Netherlands
- Department of Internal Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Vilmundur Gudnason
- Icelandic Heart Association, Kopavogur, Iceland
- Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | - Eric S Orwoll
- Division of Endocrinology, Oregon Health & Science University, Portland, OR, USA
| | - Tamara B Harris
- National Institute on Aging (NIA), National Institutes of Health, Bethesda, MD, USA
| | - Claes Ohlsson
- Centre for Bone and Arthritis Research, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Douglas P Kiel
- Institute for Aging Research, Hebrew SeniorLife, Harvard Medical School, Boston, MA, USA
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard University Medical School, Boston, MA, USA
| | - Yi-Hsiang Hsu
- Institute for Aging Research, Hebrew SeniorLife, Harvard Medical School, Boston, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA, USA
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10
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Wnt3a-producing fibroblasts in ovariectomy-induced osteoporosis in a rat model. Tissue Eng Regen Med 2015. [DOI: 10.1007/s13770-014-0074-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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11
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Kantaputra PN, Kaewgahya M, Hatsadaloi A, Vogel P, Kawasaki K, Ohazama A, Ketudat Cairns JR. GREMLIN 2 Mutations and Dental Anomalies. J Dent Res 2015; 94:1646-52. [PMID: 26416033 DOI: 10.1177/0022034515608168] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Isolated or nonsyndromic tooth agenesis or hypodontia is the most common human malformation. It has been associated with mutations in MSX1, PAX9, EDA, AXIN2, EDAR, EDARADD, and WNT10A. GREMLIN 2 (GREM2) is a strong bone morphogenetic protein (BMP) antagonist that is known to regulate BMPs in embryogenesis and tissue development. Bmp4 has been shown to have a role in tooth development. Grem2(-/-) mice have small, malformed maxillary and mandibular incisors, indicating that Grem2 has important roles in normal tooth development. Here, we demonstrate for the first time that GREM2 mutations are associated with human malformations, which include isolated tooth agenesis, microdontia, short tooth roots, taurodontism, sparse and slow-growing hair, and dry and itchy skin. We sequenced WNT10A, WNT10B, MSX1, EDA, EDAR, EDARADD, AXIN2, and PAX9 in all 7 patients to rule out the effects of other ectodermal dysplasias and other tooth-related genes and did not find mutations in any of them. GREM2 mutations exhibit variable expressivity even within the same families. The inheritance is autosomal dominant with incomplete penetrance. The expression of Grem2 during the early development of mouse teeth and hair follicles and the evaluation of the likely effects of the mutations on the protein structure substantiate these new findings.
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Affiliation(s)
- P N Kantaputra
- Center of Excellence in Medical Genetics Research, Chiang Mai University, Chiang Mai, Thailand Division of Pediatric Dentistry, Department of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand Dentaland Clinic, Chiang Mai, Thailand
| | - M Kaewgahya
- Center of Excellence in Medical Genetics Research, Chiang Mai University, Chiang Mai, Thailand Division of Pediatric Dentistry, Department of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
| | | | - P Vogel
- Department of Veterinary Pathology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - K Kawasaki
- Division of Oral Anatomy, Department of Oral Biological Science, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
| | - A Ohazama
- Division of Oral Anatomy, Department of Oral Biological Science, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
| | - J R Ketudat Cairns
- School of Biochemistry, Institute of Science, and Center for Biomolecular Structure, Function and Application, Suranaree University of Technology, Nakhon Ratchasima, Thailand Laboratory of Biochemistry, Chulabhorn Research Institute, Bangkok, Thailand
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12
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Vogel P, Liu J, Platt KA, Read RW, Thiel M, Vance RB, Brommage R. Malformation of Incisor Teeth in Grem2-/- Mice. Vet Pathol 2014; 52:224-9. [DOI: 10.1177/0300985814528218] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
GREMLIN 2 ( GREM2)—formerly, protein related to Dan and cerberus ( PRDC)—is a potent antagonist of the bone morphogenetic proteins 2 and 4, but little else in known about its functions. We found that Grem2-/- mice developed small deformed mandibular and maxillary incisors, indicating that GREMLIN2 is required for normal tooth morphogenesis. Although DEXA scans suggested that bone mineral density might be increased in Grem2-/- mice, histology did not reveal any evident bone phenotype. Grem2-/- mice did not display any other notable phenotypes evaluated in a high-throughput screening process that encompassed a range of immunologic, metabolic, ophthalmic, and behavioral parameters. Our findings indicate that Grem2 can be added to the growing list of genes that affect tooth development in mice.
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Affiliation(s)
- P. Vogel
- Department of Pathology, Lexicon Pharmaceuticals Inc, The Woodlands, TX, USA
| | - J. Liu
- Department of Metabolism, Lexicon Pharmaceuticals Inc, The Woodlands, TX, USA
| | - K. A. Platt
- Department of Molecular Genetics, Lexicon Pharmaceuticals Inc, The Woodlands, TX, USA
| | - R. W. Read
- Department of Pathology, Lexicon Pharmaceuticals Inc, The Woodlands, TX, USA
| | - M. Thiel
- Department of Pathology, Lexicon Pharmaceuticals Inc, The Woodlands, TX, USA
| | - R. B. Vance
- Department of Pathology, Lexicon Pharmaceuticals Inc, The Woodlands, TX, USA
| | - R. Brommage
- Department of Metabolism, Lexicon Pharmaceuticals Inc, The Woodlands, TX, USA
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13
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Starostová M, Cermák V, Dvořáková M, Karafiát V, Kosla J, Dvořák M. The oncoprotein v-Myb activates transcription of Gremlin 2 during in vitro differentiation of the chicken neural crest to melanoblasts. Gene 2014; 540:122-9. [PMID: 24576577 DOI: 10.1016/j.gene.2014.02.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 02/18/2014] [Accepted: 02/21/2014] [Indexed: 01/09/2023]
Abstract
The neural crest (NC) is a transient dynamic structure of ectodermal origin, found in early vertebrate embryos. The multipotential NC cells migrate along well defined routes, differentiate to various cell types including melanocytes and participate in the formation of various permanent tissues. As there is only limited information about the molecular mechanisms controlling early events in melanocyte specification and development, we exploited the AMV v-Myb transcriptional regulator, which directs differentiation of in vitro chicken NC cells to the melanocyte lineage. This activity is strictly dependent on v-Myb specifically binding to the Myb recognition DNA element (MRE). The two tamoxifen-inducible v-Myb alleles were constructed one which recognizes the MRE and one which does not. These were activated in ex ovo NC cells, and the expression profiles of resulting cells were analyzed using Affymetrix microarrays and RT-PCR. These approaches revealed up-regulation of the BMP antagonist Gremlin 2 mRNA, and down-regulation of mRNAs encoding several epithelial genes including KRT19 as very early events following the activation of melanocyte differentiation by v-Myb. The enforced v-Myb expression in neural tubes of chicken embryos resulted in detectable presence of Gremlin 2 mRNA. However, expression of Gremlin 2 in NC cells did not promote formation of melanocytes suggesting that Gremlin 2 is not the master regulator of melanocytic differentiation.
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Affiliation(s)
- Michaela Starostová
- Institute of Molecular Genetics AS CR, v.v.i., Department of Molecular Virology, Vídeňská 1083, Praha 4 142 20, Czech Republic.
| | - Vladimír Cermák
- Institute of Molecular Genetics AS CR, v.v.i., Department of Molecular Virology, Vídeňská 1083, Praha 4 142 20, Czech Republic.
| | - Marta Dvořáková
- Institute of Molecular Genetics AS CR, v.v.i., Department of Molecular Virology, Vídeňská 1083, Praha 4 142 20, Czech Republic.
| | - Vít Karafiát
- Institute of Molecular Genetics AS CR, v.v.i., Department of Molecular Virology, Vídeňská 1083, Praha 4 142 20, Czech Republic.
| | - Jan Kosla
- Institute of Molecular Genetics AS CR, v.v.i., Department of Molecular Virology, Vídeňská 1083, Praha 4 142 20, Czech Republic.
| | - Michal Dvořák
- Institute of Molecular Genetics AS CR, v.v.i., Department of Molecular Virology, Vídeňská 1083, Praha 4 142 20, Czech Republic.
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14
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Rolfe RA, Nowlan NC, Kenny EM, Cormican P, Morris DW, Prendergast PJ, Kelly D, Murphy P. Identification of mechanosensitive genes during skeletal development: alteration of genes associated with cytoskeletal rearrangement and cell signalling pathways. BMC Genomics 2014; 15:48. [PMID: 24443808 PMCID: PMC3905281 DOI: 10.1186/1471-2164-15-48] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 12/18/2013] [Indexed: 12/15/2022] Open
Abstract
Background Mechanical stimulation is necessary for regulating correct formation of the skeleton. Here we test the hypothesis that mechanical stimulation of the embryonic skeletal system impacts expression levels of genes implicated in developmentally important signalling pathways in a genome wide approach. We use a mutant mouse model with altered mechanical stimulation due to the absence of limb skeletal muscle (Splotch-delayed) where muscle-less embryos show specific defects in skeletal elements including delayed ossification, changes in the size and shape of cartilage rudiments and joint fusion. We used Microarray and RNA sequencing analysis tools to identify differentially expressed genes between muscle-less and control embryonic (TS23) humerus tissue. Results We found that 680 independent genes were down-regulated and 452 genes up-regulated in humeri from muscle-less Spd embryos compared to littermate controls (at least 2-fold; corrected p-value ≤0.05). We analysed the resulting differentially expressed gene sets using Gene Ontology annotations to identify significant enrichment of genes associated with particular biological processes, showing that removal of mechanical stimuli from muscle contractions affected genes associated with development and differentiation, cytoskeletal architecture and cell signalling. Among cell signalling pathways, the most strongly disturbed was Wnt signalling, with 34 genes including 19 pathway target genes affected. Spatial gene expression analysis showed that both a Wnt ligand encoding gene (Wnt4) and a pathway antagonist (Sfrp2) are up-regulated specifically in the developing joint line, while the expression of a Wnt target gene, Cd44, is no longer detectable in muscle-less embryos. The identification of 84 genes associated with the cytoskeleton that are down-regulated in the absence of muscle indicates a number of candidate genes that are both mechanoresponsive and potentially involved in mechanotransduction, converting a mechanical stimulus into a transcriptional response. Conclusions This work identifies key developmental regulatory genes impacted by altered mechanical stimulation, sheds light on the molecular mechanisms that interpret mechanical stimulation during skeletal development and provides valuable resources for further investigation of the mechanistic basis of mechanoregulation. In particular it highlights the Wnt signalling pathway as a potential point of integration of mechanical and molecular signalling and cytoskeletal components as mediators of the response.
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Affiliation(s)
| | | | | | | | | | | | | | - Paula Murphy
- Department of Zoology, School of Natural Sciences, Trinity College Dublin, Dublin, Ireland.
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15
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Guirguis E, Hockman S, Chung YW, Ahmad F, Gavrilova O, Raghavachari N, Yang Y, Niu G, Chen X, Yu ZX, Liu S, Degerman E, Manganiello V. A role for phosphodiesterase 3B in acquisition of brown fat characteristics by white adipose tissue in male mice. Endocrinology 2013; 154:3152-67. [PMID: 23766131 PMCID: PMC3749478 DOI: 10.1210/en.2012-2185] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Obesity is linked to various diseases, including insulin resistance, diabetes, and cardiovascular disorders. The idea of inducing white adipose tissue (WAT) to assume characteristics of brown adipose tissue (BAT), and thus gearing it to fat burning instead of storage, is receiving serious consideration as potential treatment for obesity and related disorders. Phosphodiesterase 3B (PDE3B) links insulin- and cAMP-signaling networks in tissues associated with energy metabolism, including WAT. We used C57BL/6 PDE3B knockout (KO) mice to elucidate mechanisms involved in the formation of BAT in epididymal WAT (EWAT) depots. Examination of gene expression profiles in PDE3B KO EWAT revealed increased expression of several genes that block white and promote brown adipogenesis, such as C-terminal binding protein, bone morphogenetic protein 7, and PR domain containing 16, but a clear BAT-like phenotype was not completely induced. However, acute treatment of PDE3B KO mice with the β3-adrenergic agonist, CL316243, markedly increased the expression of cyclooxygenase-2, which catalyzes prostaglandin synthesis and is thought to be important in the formation of BAT in WAT and the elongation of very long-chain fatty acids 3, which is linked to BAT recruitment upon cold exposure, causing a clear shift toward fat burning and the induction of BAT in KO EWAT. These data provide insight into the mechanisms of BAT formation in mouse EWAT, suggesting that, in a C57BL/6 background, an increase in cAMP, caused by ablation of PDE3B and administration of CL316243, may promote differentiation of prostaglandin-responsive progenitor cells in the EWAT stromal vascular fraction into functional brown adipocytes.
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MESH Headings
- Adipogenesis/drug effects
- Adipose Tissue, Brown/cytology
- Adipose Tissue, Brown/drug effects
- Adipose Tissue, Brown/metabolism
- Adipose Tissue, White/cytology
- Adipose Tissue, White/drug effects
- Adipose Tissue, White/metabolism
- Adrenergic beta-3 Receptor Agonists/pharmacology
- Adult Stem Cells/cytology
- Adult Stem Cells/drug effects
- Adult Stem Cells/metabolism
- Animals
- Biomarkers/metabolism
- Crosses, Genetic
- Cyclic AMP/metabolism
- Cyclic Nucleotide Phosphodiesterases, Type 3/chemistry
- Cyclic Nucleotide Phosphodiesterases, Type 3/genetics
- Cyclic Nucleotide Phosphodiesterases, Type 3/metabolism
- Cyclooxygenase 2/biosynthesis
- Cyclooxygenase 2/genetics
- Cyclooxygenase 2/metabolism
- Dioxoles/pharmacology
- Enzyme Induction/drug effects
- Epididymis
- Gene Expression Profiling
- Male
- Mice
- Mice, 129 Strain
- Mice, Inbred C57BL
- Mice, Knockout
- Phosphodiesterase Inhibitors/pharmacology
- Quinolones/pharmacology
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Affiliation(s)
- Emilia Guirguis
- Pulmonary Cardiovascular Branch, National Institutes of Health, Bethesda, Maryland 20892, USA.
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16
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Park JH, Min J, Baek SR, Kim SW, Kwon IK, Jeon SR. Enhanced neuroregenerative effects by scaffold for the treatment of a rat spinal cord injury with Wnt3a-secreting fibroblasts. Acta Neurochir (Wien) 2013; 155:809-16. [PMID: 23456240 DOI: 10.1007/s00701-013-1663-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Accepted: 02/18/2013] [Indexed: 12/29/2022]
Abstract
BACKGROUND Wnt proteins are bifunctional axon guidance molecules, several of which appear to mediate guidance of corticospinal tract axons along the spinal cord. Here, we studied increasing effect on regeneration by Wnt-containing alginate scaffolds on spinal cord injury (SCI). METHODS A total of 32 rats were injured at the T7-8 level with an NYU impactor. According to transplantation materials, rats were classified into four groups: a Wnt3a-secreting fibroblast transplantation group (Wnt group, n = 8), a Wnt3a-secreting fibroblast with alginate transplantation group (Wnt + alginate group, n = 8), an alginate transplantation group (alginate group, n = 8), and a contusion-only group (sham group, n = 8). Behavioral tests were performed on the first, second, and third days after injury, and then weekly for 8 weeks. Five of the eight rats from each group were selected for manganese-enhanced magnetic resonance imaging (ME-MRI). Two rats from each group were examined for GAP43 and MAP2 expression using monoclonal and polyclonal primary antibodies, respectively. RESULTS Seven weeks after transplantation (8 weeks after SCI), Wnt + alginate group rats achieved an average Basso-Beattie-Bresnahan locomotor score of 19.0, which was significantly higher than that of other groups. ME-MRI at 8 weeks after SCI revealed significantly higher relative signal intensities in the Wnt + alginate group. Gap43 and Map2 immunostaining, showed strong positive in the Wnt + alginate group. CONCLUSION The Wnt + alginate complex exerted significantly enhanced recovery in a rat SCI model compared to alginate or Wnt3a alone. These results suggest that alginate scaffolds facilitate the regeneration of axon working with Wnt3a protein that promotes regeneration of the injured spinal cord.
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17
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Genetic determinants of trabecular and cortical volumetric bone mineral densities and bone microstructure. PLoS Genet 2013; 9:e1003247. [PMID: 23437003 PMCID: PMC3578773 DOI: 10.1371/journal.pgen.1003247] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 12/02/2012] [Indexed: 11/24/2022] Open
Abstract
Most previous genetic epidemiology studies within the field of osteoporosis have focused on the genetics of the complex trait areal bone mineral density (aBMD), not being able to differentiate genetic determinants of cortical volumetric BMD (vBMD), trabecular vBMD, and bone microstructural traits. The objective of this study was to separately identify genetic determinants of these bone traits as analysed by peripheral quantitative computed tomography (pQCT). Separate GWA meta-analyses for cortical and trabecular vBMDs were performed. The cortical vBMD GWA meta-analysis (n = 5,878) followed by replication (n = 1,052) identified genetic variants in four separate loci reaching genome-wide significance (RANKL, rs1021188, p = 3.6×10−14; LOC285735, rs271170, p = 2.7×10−12; OPG, rs7839059, p = 1.2×10−10; and ESR1/C6orf97, rs6909279, p = 1.1×10−9). The trabecular vBMD GWA meta-analysis (n = 2,500) followed by replication (n = 1,022) identified one locus reaching genome-wide significance (FMN2/GREM2, rs9287237, p = 1.9×10−9). High-resolution pQCT analyses, giving information about bone microstructure, were available in a subset of the GOOD cohort (n = 729). rs1021188 was significantly associated with cortical porosity while rs9287237 was significantly associated with trabecular bone fraction. The genetic variant in the FMN2/GREM2 locus was associated with fracture risk in the MrOS Sweden cohort (HR per extra T allele 0.75, 95% confidence interval 0.60–0.93) and GREM2 expression in human osteoblasts. In conclusion, five genetic loci associated with trabecular or cortical vBMD were identified. Two of these (FMN2/GREM2 and LOC285735) are novel bone-related loci, while the other three have previously been reported to be associated with aBMD. The genetic variants associated with cortical and trabecular bone parameters differed, underscoring the complexity of the genetics of bone parameters. We propose that a genetic variant in the RANKL locus influences cortical vBMD, at least partly, via effects on cortical porosity, and that a genetic variant in the FMN2/GREM2 locus influences GREM2 expression in osteoblasts and thereby trabecular number and thickness as well as fracture risk. Osteoporosis is a common highly heritable skeletal disease characterized by reduced bone mineral density (BMD) and deteriorated bone microstructure, resulting in an increased risk of fracture. Most previous genetic epidemiology studies have focused on the genetics of the complex trait BMD, not being able to separate genetic determinants of the trabecular and cortical bone compartments and bone microstructure. The trabecular and cortical BMDs can be analysed separately by computed tomography. Therefore, we performed separate genome-wide association studies for trabecular and cortical BMDs, demonstrating that the genetic determinants of cortical and trabecular BMDs differ. Genetic variants in the RANKL, LOC285735, OPG, and ESR1 loci were associated with cortical BMD, while a genetic variant in the FMN2/GREM2 locus was associated with trabecular BMD. Two of these are novel bone-related loci. Follow-up analyses of bone microstructure demonstrated that a genetic variant in the RANKL locus is associated with cortical porosity and that the FMN2/GREM2 locus is associated with trabecular number and thickness. We propose that a genetic variant in the RANKL locus influences cortical BMD via effects on cortical porosity, and that a genetic variant in the FMN2/GREM2 locus influences trabecular BMD and fracture risk via effects on both trabecular number and thickness.
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18
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Yu B, Zhao X, Yang C, Crane J, Xian L, Lu W, Wan M, Cao X. Parathyroid hormone induces differentiation of mesenchymal stromal/stem cells by enhancing bone morphogenetic protein signaling. J Bone Miner Res 2012; 27:2001-14. [PMID: 22589223 PMCID: PMC3423493 DOI: 10.1002/jbmr.1663] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Parathyroid hormone (PTH) stimulates bone remodeling and induces differentiation of bone marrow mesenchymal stromal/stem cells (MSCs) by orchestrating activities of local factors such as bone morphogenetic proteins (BMPs). The activity and specificity of different BMP ligands are controlled by various extracellular antagonists that prevent binding of BMPs to their receptors. Low-density lipoprotein receptor-related protein 6 (LRP6) has been shown to interact with both the PTH and BMP extracellular signaling pathways by forming a complex with parathyroid hormone 1 receptor (PTH1R) and sharing common antagonists with BMPs. We hypothesized that PTH-enhanced differentiation of MSCs into the osteoblast lineage through enhancement of BMP signaling occurs by modifying the extracellular antagonist network via LRP6. In vitro studies using multiple cell lines, including Sca-1(+) CD45(-) CD11b(-) MSCs, showed that a single injection of PTH enhanced phosphorylation of Smad1 and could also antagonize the inhibitory effect of noggin. PTH treatment induced endocytosis of a PTH1R/LRP6 complex and resulted in enhancement of phosphorylation of Smad1 that was abrogated by deletion of PTH1R, β-arrestin, or chlorpromazine. Deletion of LRP6 alone led to enhancement of pSmad1 levels that could not be further increased with PTH treatment. Finally, knockdown of LRP6 increased the exposure of endogenous cell-surface BMP receptor type II (BMPRII) significantly in C2C12 cells, and PTH treatment significantly enhanced cell-surface binding of (125) I-BMP2 in a dose- and time-dependent manner, implying that LRP6 organizes an extracellular network of BMP antagonists that prevent access of BMPs to BMP receptors. In vivo studies in C57BL/6J mice and of transplanted green fluorescent protein (GFP)-labeled Sca-1(+) CD45(-) CD11b(-) MSCs into the bone marrow cavity of Rag2(-/-) immunodeficient mice showed that PTH enhanced phosphorylation of Smad1 and increased commitment of MSCs to osteoblast lineage, respectively. These data demonstrate that PTH enhancement of MSC differentiation to the osteoblast lineage occurs through a PTH- and LRP6-dependent pathway by endocytosis of the PTH1R/LRp6 complex, allowing enhancement of BMP signaling.
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Affiliation(s)
- Bing Yu
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Xiaoli Zhao
- Department of Orthopaedics and Traumatology, University of Hong Kong, Hong Kong, China
| | - Chaozhe Yang
- Center for Clinical and Community Research, Children’s National Medical Center, Washington, DC, USA
| | - Janet Crane
- Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Lingling Xian
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - William Lu
- Department of Orthopaedics and Traumatology, University of Hong Kong, Hong Kong, China
| | - Mei Wan
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Xu Cao
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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19
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Kattamuri C, Luedeke DM, Thompson TB. Expression and purification of recombinant protein related to DAN and cerberus (PRDC). Protein Expr Purif 2012; 82:389-95. [PMID: 22381466 DOI: 10.1016/j.pep.2012.02.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 02/10/2012] [Accepted: 02/11/2012] [Indexed: 10/28/2022]
Abstract
Bone morphogenetic proteins (BMPs) are secreted protein ligands that control numerous biological processes, such as cell differentiation and cell proliferation. Ligands are regulated by a large number of structurally diverse extracellular antagonists. PRDC or protein related to DAN and cerberus is a BMP antagonist of the DAN family, which is defined by a conserved pattern of cysteine residues that form a ring structure. Here we present the expression and purification of recombinant mouse PRDC (mPRDC) from bacterial (Escherichia coli) inclusion bodies through oxidative refolding. Functional mPRDC was isolated from a nonfunctional component through reverse phase chromatography and shown to inhibit BMP2 and BMP4 in a cell-based luciferase reporter assay. Recombinant mPRDC also bound directly to BMP2, BMP4 and BMP7, but not activin A. Furthermore, circular dichroism indicated that mPRDC is folded and contains a higher than anticipated helical content for a DAN family member protein.
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Affiliation(s)
- Chandramohan Kattamuri
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati Medical Sciences Building, Cincinnati, OH 45267, United States
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20
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Axonal regeneration effects of Wnt3a-secreting fibroblast transplantation in spinal cord-injured rats. Acta Neurochir (Wien) 2011; 153:1003-10. [PMID: 21249402 DOI: 10.1007/s00701-011-0945-1] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Accepted: 01/06/2011] [Indexed: 12/29/2022]
Abstract
BACKGROUND Axonal regeneration is a prerequisite for recovery from spinal cord injury. Here, we investigated whether Wnt3a-secreting fibroblasts exert a favorable effect on spinal cord regeneration in spinal cord-injured rats. METHODS Spinal cord injury (SCI) was induced in rats (n = 21) using an NYU impactor. One week after SCI, rats were assigned to a Wnt3a-secreting fibroblast transplantation group (Wnt group, n = 7), a L929 fibroblast transplantation group (vehicle group, n = 7), and contusion only group (sham group, n = 7). Motor function was tested weekly for 6 weeks. Manganese-enhanced magnetic resonance imaging (ME-MRI) was performed twice, once before cell transplantation and again 5 weeks after cell transplantation. After ME-MRI, expression of the axonal regeneration marker GAP-43 was assessed by immunohistochemistry (IHC). RESULTS In the Wnt group, the mean Basso-Beattie-Bresnahan score was higher than that of the vehicle and sham groups throughout the observation period. The Wnt group also exhibited stronger signal intensity on ME-MRI, and IHC revealed that GAP-43 was highly expressed in the injured spinal cord in the Wnt group. CONCLUSIONS These results strongly suggest that transplanted Wnt3a secreting fibroblasts promote axonal regeneration and functional improvement after SCI. Although further investigation will be necessary to clarify the intracellular mechanism by which Wnt signaling promotes axonal regeneration and functional improvement, this approach could be a highly promising therapeutic strategy for SCI.
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Kim M, Kim H, Jho EH. Identification of ptpro as a novel target gene of Wnt signaling and its potential role as a receptor for Wnt. FEBS Lett 2010; 584:3923-8. [PMID: 20804755 DOI: 10.1016/j.febslet.2010.08.034] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Revised: 08/19/2010] [Accepted: 08/21/2010] [Indexed: 01/01/2023]
Abstract
Wnt/β-catenin signaling plays critical roles in embryonic development and tissue homeostasis in adults by controlling the expression of target genes. We found that expression of ptpro, which encodes a protein tyrosine phosphatase receptor type O (PTPRO), was induced by Wnt/β-catenin signaling in a T cell factor/lymphoid enhancer factor dependent manner. Biochemical assays found that PTPRO interacted with Wnt via its extracellular domain. In addition, ectopic expression of this extracellular domain inhibited Wnt-mediated reporter activity. These results suggest that ptpro is a target gene of Wnt/β-catenin signaling and that PTPRO may function as a novel receptor for Wnt.
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Affiliation(s)
- Minseong Kim
- Department of Life Science, The University of Seoul, Seoul, Republic of Korea
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Itasaki N, Hoppler S. Crosstalk between Wnt and bone morphogenic protein signaling: a turbulent relationship. Dev Dyn 2010; 239:16-33. [PMID: 19544585 DOI: 10.1002/dvdy.22009] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The Wnt and the bone morphogenic protein (BMP) pathways are evolutionarily conserved and essentially independent signaling mechanisms, which, however, often regulate similar biological processes. Wnt and BMP signaling are functionally integrated in many biological processes, such as embryonic patterning in Drosophila and vertebrates, formation of kidney, limb, teeth and bones, maintenance of stem cells, and cancer progression. Detailed inspection of regulation in these and other tissues reveals that Wnt and BMP signaling are functionally integrated in four fundamentally different ways. The molecular mechanism evolved to mediate this integration can also be summarized in four different ways. However, a fundamental aspect of functional and mechanistic interaction between these pathways relies on tissue-specific mechanisms, which are often not conserved and cannot be extrapolated to other tissues. Integration of the two pathways contributes toward the sophisticated means necessary for creating the complexity of our bodies and the reliable and healthy function of its tissues and organs.
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Affiliation(s)
- Nobue Itasaki
- Division of Developmental Neurobiology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom.
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Extracellular BMP-antagonist regulation in development and disease: tied up in knots. Trends Cell Biol 2010; 20:244-56. [PMID: 20188563 DOI: 10.1016/j.tcb.2010.01.008] [Citation(s) in RCA: 182] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 01/20/2010] [Accepted: 01/20/2010] [Indexed: 01/11/2023]
Abstract
Developmental processes are regulated by the bone morphogenetic protein (BMP) family of secreted molecules. BMPs bind to serine/threonine kinase receptors and signal through the canonical Smad pathway and other intracellular effectors. Integral to the control of BMPs is a diverse group of secreted BMP antagonists that bind to BMPs and prevent engagement with their cognate receptors. Tight temporospatial regulation of both BMP and BMP-antagonist expression provides an exquisite control system for developing tissues. Additional facets of BMP-antagonist biology, such as crosstalk with Wnt and Sonic hedgehog signaling during development, have been revealed in recent years. In addition, previously unappreciated roles for the BMP antagonists in kidney fibrosis and cancer have been elucidated. This review provides a description of BMP-antagonist biology, together with highlights of recent novel insights into the role of these antagonists in development, signal transduction and human disease.
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Ideno H, Takanabe R, Shimada A, Imaizumi K, Araki R, Abe M, Nifuji A. Protein related to DAN and cerberus (PRDC) inhibits osteoblastic differentiation and its suppression promotes osteogenesis in vitro. Exp Cell Res 2009; 315:474-84. [DOI: 10.1016/j.yexcr.2008.11.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Revised: 11/18/2008] [Accepted: 11/23/2008] [Indexed: 10/21/2022]
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Yun S, Rim Y, Jho EH. Induced expression of the transcription of tropomodulin 1 by Wnt5a and characterization of the tropomodulin 1 promoter. Biochem Biophys Res Commun 2007; 363:727-32. [PMID: 17904105 DOI: 10.1016/j.bbrc.2007.09.033] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2007] [Accepted: 09/09/2007] [Indexed: 10/22/2022]
Abstract
Microarray analysis was carried out to identify novel downstream target genes regulated by non-canonical Wnt signaling. We found that Tmod1, known as an actin-capping protein, is up-regulated by Wnt5a, while gelsolin, known as an actin-severing protein, is down-regulated by Wnt5a. As expected from the roles of genes regulated by Wnt5a, L929 cells expressing Wnt5a show abnormal cell shape and a reduced migration rate. Cloning and analysis of the putative promoter show that two conserved sequences, one in the 5'-end of the first exon and the other in the intron next to the first exon, are necessary for the basal promoter activity.
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Affiliation(s)
- Sangmoon Yun
- Department of Life Science, The University of Seoul, 90 Jeonnong-dong, Dongdaemun-gu, Seoul 130-743, Republic of Korea
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Klapholz-Brown Z, Walmsley GG, Nusse YM, Nusse R, Brown PO. Transcriptional program induced by Wnt protein in human fibroblasts suggests mechanisms for cell cooperativity in defining tissue microenvironments. PLoS One 2007; 2:e945. [PMID: 17895986 PMCID: PMC1976560 DOI: 10.1371/journal.pone.0000945] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Accepted: 09/02/2007] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The Wnt signaling system plays key roles in development, regulation of stem cell self-renewal and differentiation, cell polarity, morphogenesis and cancer. Given the multifaceted roles of Wnt signaling in these processes, its transcriptional effects on the stromal cells that make up the scaffold and infrastructure of epithelial tissues are of great interest. METHODS AND RESULTS To begin to investigate these effects, we used DNA microarrays to identify transcriptional targets of the Wnt pathway in human lung fibroblasts. Cells were treated with active Wnt3a protein in culture, and RNA was harvested at 4 hours and 24 hours. Nuclear accumulation of ss-Catenin, as shown by immunofluorescence, and induction of AXIN2 demonstrate that fibroblasts are programmed to respond to extracellular Wnt signals. In addition to several known Wnt targets, we found many new Wnt induced genes, including many transcripts encoding regulatory proteins. Transcription factors with important developmental roles, including HOX genes, dominated the early transcriptional response. Furthermore, we found differential expression of several genes that play direct roles in the Wnt signaling pathway, as well as genes involved in other cell signaling pathways including fibroblast growth factor (FGF) and bone morphogenetic protein (BMP) signaling. The gene most highly induced by Wnt3a was GREMLIN2, which encodes a secreted BMP antagonist. CONCLUSIONS Elevated expression of GREMLIN2 suggests a new role for Wnt signals in the maintenance of stem cell niches, whereby Wnt signals induce nearby fibroblasts to produce a BMP antagonist, inhibiting differentiation and promoting expansion of stem cells in their microenvironment. We suggest that Wnt-induced changes in the gene expression program of local stromal cells may play an important role in the establishment of specialized niches hospitable to the self-renewal of normal or malignant epithelial stem cells in vivo.
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Affiliation(s)
- Zach Klapholz-Brown
- Department of Biochemistry, Stanford University School of Medicine, Stanford, California, USA.
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